A rare earth nanoparticle magnetic resonance contrast agent and a preparation method thereof. The rare earth nanoparticle magnetic resonance contrast agent is a rare earth inorganic nanoparticle coated on the surface with a hydrophilic ligand and is prepared by the following method: After obtaining rare earth nanoparticles by oil phase reaction at high temperature, It is obtained by coating the surface with hydrophilic molecules. The magnetic resonance contrast agent has a remarkably improved relaxation rate as compared with the conventional clinical contrast agent, has a good imaging effect, a small desired injection volume and a long staying time in the body. In addition, due to the rigid structure of the inorganic nanoparticles, the possibility of release of gadolinium ions can be effectively reduced.(FIG.希土類ナノ粒子磁気共鳴造影剤及びその調製方法を提供する。該希土類ナノ粒子磁気共鳴造影剤は、表面に親水性リガンドで被覆された希土類無機ナノ粒子であって、以下の方法により調製される:高温で油相反応によって希土類ナノ粒子を取得してから、その表面に親水性分子を被覆すると得られる。該磁気共鳴造影剤は、従来の臨床的な造影剤に比べ、緩和率が大きく向上し、結像効果が良く、所望の注射分量が小さく、且つ体内での停留時間が長い。また、無機ナノ粒子の剛性構造により、ガドリニウムイオンの遊離可能性を効果的に低下させることができる。【選択図】図5
